40 years ago,a small collective economic workshop was set up in Shijie Town(now Shijie Street)in Ningbo,called Youth Garment Factory.Today,40 years later,this small workshop has already become a company with more than...40 years ago,a small collective economic workshop was set up in Shijie Town(now Shijie Street)in Ningbo,called Youth Garment Factory.Today,40 years later,this small workshop has already become a company with more than 50,000 employees and an annual output of 50 million shirts and a revenue of 87.9 billion yuan in 2018,Youngor,a Chinese top 500 enterprise that spans textile,clothing,real estate,investment and trade.展开更多
May 23 marks the 43rd anniversary of the peaceful liberation of Tibet.A spokesman for the United Front Work Department of the CPC Central Commit-tee recently spoke to a Xinhua reporter on development and construction ...May 23 marks the 43rd anniversary of the peaceful liberation of Tibet.A spokesman for the United Front Work Department of the CPC Central Commit-tee recently spoke to a Xinhua reporter on development and construction in the Tibet Autonomous Region and the cen-tral government's policy on the Dalai L ama.展开更多
When calcium ions enter the cytosol,it is a stimulatory signal for cellular events.The calcium sensor calmodulin picks up the change in calcium concentration and relays this information to its more than 300 downstream...When calcium ions enter the cytosol,it is a stimulatory signal for cellular events.The calcium sensor calmodulin picks up the change in calcium concentration and relays this information to its more than 300 downstream interaction partners.In this way,calmodulin affects cellular processes such as fertilization,muscle contraction,neuronal firing,and apoptosis.That is,calmodulin is involved in(nearly)everything!The significance of calmodulin is emphasized by the fact that we all carry three different genes(CALM1,2,3)on different chromosomes that encode the exact same calmodulin protein,and these are all expressed in all cell types.Moreover,throughout vertebrate evolution,the protein sequence has remained completely unchanged.展开更多
No matter how the world changes,people’s aspiration for a better living environment remains unchanged.Urban planners factor this in their blueprints and different eras give different characteristics to urban design a...No matter how the world changes,people’s aspiration for a better living environment remains unchanged.Urban planners factor this in their blueprints and different eras give different characteristics to urban design and architecture.Modernization,technological progress,cultural trends,and social issues have all become drivers of urban planning and building design.In addition,architects and urban planners worldwide have to consider several crucial issues today-how to tackle climate change by reducing carbon emission in construction and improving the ecological environment in urban design,how to revitalize ancient cultural heritage,and how to create a new,sustainable urban culture.展开更多
As shown in the results of the survey of the confidence of 100 Chinese economists,conducted by China’s Economic Monitoring and Analysis Centre,National Bureau of Statistics,the confidence index of the economists in t...As shown in the results of the survey of the confidence of 100 Chinese economists,conducted by China’s Economic Monitoring and Analysis Centre,National Bureau of Statistics,the confidence index of the economists in the second quarter of 2009 was 5.60,the range of possible indices being from 1 to 9.It was 1.63 points higher than that of the first quarter,continuing the stabilized situation with a trend of rising again.The situation had appeared since the beginning of 2009.展开更多
Physical activity has many benefits for individual health and well-being,including a reduced risk of noncommunicable diseases,as well as improved mental health,sleep,and cognitive function.1 Being physically active al...Physical activity has many benefits for individual health and well-being,including a reduced risk of noncommunicable diseases,as well as improved mental health,sleep,and cognitive function.1 Being physically active also has broader social and environmental benefits and has a key role to play in achieving the 2030 Sustainable Development Goals.2,3 However,over 80%of adolescents and around a quarter of adults are insufficiently active and these figures have remained largely unchanged for the past 20 years.4,5 A recent economic analysis estimated that the total cost of inactive lifestyles equates to USD 27 billion(INT 48 billion)annually.展开更多
At the recent routine press conference of the CCPIT in October, CCPIT spokesperson Zhang Xin stated that China’s foreign trade operated smoothly for the first three quarters of this year, with a year-on-year growth r...At the recent routine press conference of the CCPIT in October, CCPIT spokesperson Zhang Xin stated that China’s foreign trade operated smoothly for the first three quarters of this year, with a year-on-year growth rate that remained basically unchanged and showed a positive development trend.展开更多
IN an ancient town in the southern reaches of the Yangtze River there lived in a small compound of nine average households sharing an ancient well.e layout of the oldstyle houses had largely remained unchanged over th...IN an ancient town in the southern reaches of the Yangtze River there lived in a small compound of nine average households sharing an ancient well.e layout of the oldstyle houses had largely remained unchanged over the years, except that more and more modern furniture and home décor accessories had been added.展开更多
China’s policy of reform and opening up will remain unchanged over the long term.——Chinese President Xi Jinping April 13,2023 while inspecting Guangdong Province Measures of high-standard opening up Xi noted,in his...China’s policy of reform and opening up will remain unchanged over the long term.——Chinese President Xi Jinping April 13,2023 while inspecting Guangdong Province Measures of high-standard opening up Xi noted,in his report to the 20th CPC National Congress,that in order to promote high-standard opening up,China will·leverage the strengths of China’s enormous market,attract global resources and production factors with our strong domestic economy,and amplify the interplay between domestic and international markets and resources.展开更多
The flavonoid compounds are important secondary metabolites with versatile human nutritive benefits and fulfill a multitude of functions during plant growth and development.The abundance of different flavonoid compoun...The flavonoid compounds are important secondary metabolites with versatile human nutritive benefits and fulfill a multitude of functions during plant growth and development.The abundance of different flavonoid compounds are finely tuned with species-specific pattern by a ternary MBW complex,which consists of a MYB,a bHLH,and a WD40 protein,but the essential role of SlAN11,which is a WD40 protein,is not fully understood in tomato until now.In this study,a tomato WD40 protein named as SlAN11 was characterized as an effective transcription regulator to promote plant anthocyanin and seed proanthocyanidin(PA)contents,with late flavonoid biosynthetic genes activated in 35S::SlAN11 transgenic lines,while the dihydroflavonol flow to the accumulation of flavonols or their glycosylated derivatives was reduced by repressing the expression of SlFLS in this SlAN11-overexpressed lines.The above changes were reversed in 35S::SlAN11-RNAi transgenic lines except remained levels of flavonol compounds and SlFLS expression.Interestingly,our data revealed that SlAN11 gene could affect seed dormancy by regulating the expressions of abscisic acid(ABA)signaling-related genes SlABI3 and SlABI5,and the sensitivity to ABA treatment in seed germination is conversely changed by SlAN11-overexpressed or-downregulated lines.Yeast two-hybrid assays demonstrated that SlAN11 interacted with bHLH but not with MYB proteins in the ternary MBW complex,whereas bHLH interacted with MYB in tomato.Our results indicated that low level of anthocyanins in tomato fruits,with low expression of bHLH(SlTT8)and MYB(SlANT1 and SlAN2)genes,remain unchanged upon modification of SlAN11 gene alone in the transgenic lines.These results suggest that the tomato WD40 protein SlAN11,coordinating with bHLH and MYB proteins,plays a crucial role in the fine adjustment of the flavonoid biosynthesis and seed dormancy in tomato.展开更多
DC stray current can cause severe corrosion on buried pipelines.In this study,firstly,we deduced the equation of DC stray current interference on pipelines.Next,the cathode boundary condition was discretized with pipe...DC stray current can cause severe corrosion on buried pipelines.In this study,firstly,we deduced the equation of DC stray current interference on pipelines.Next,the cathode boundary condition was discretized with pipe elements,and corresponding experiments were designed to validate the mathematical model.Finally,the numerical simulation program BEASY was used to study the corrosion effect of DC stray current that an auxiliary anode bed generated in an impressed current cathodic protection system.The effects of crossing angle,crossing distance,distance of the two pipelines,anode output current,depth,and soil resistivity were investigated.Our results indicate that pipeline crossing substantially affects the corrosion potential of both protected and unprotected pipelines.Pipeline crossing angles,crossing distances,and anode depths,our results suggest,have no significant influence.Decreasing anode output current or soil resistivity reduces pipeline corrosion gradually.A reduction of corrosion also occurs when the distance between two parallel pipelines increases.展开更多
This erratum1 is issued by the authors to note that part(b)of Fig.1 was erroneously excluded in the published version of the manuscript.A correct version of Fig.1 is provided here.The figure caption of Fig.1 is repeat...This erratum1 is issued by the authors to note that part(b)of Fig.1 was erroneously excluded in the published version of the manuscript.A correct version of Fig.1 is provided here.The figure caption of Fig.1 is repeated here,however the captions and text of the document remain unchanged.展开更多
Jack London(1876-1916) is known as an American novelist in the early 20 th century. He lived in the gilded times that were full of different kinds of trend of thought in literature and art. His experiences made his li...Jack London(1876-1916) is known as an American novelist in the early 20 th century. He lived in the gilded times that were full of different kinds of trend of thought in literature and art. His experiences made his life more colorful. He saw the cruelty of Capitalism and spoke for Socialism with his words. His novels, The Call of the Wild, The leading character, in their own way, witnessed the survival of the fittest in their life. Jack London told the unchanged truth — the survival of the fittest in his brilliant words. It is difficult to change the world, but easy to change oneself. One adjusts to his life space with his"evolution",and one goes in a new environment where every cloud has a silver lining.展开更多
We focus on several aspects concerning the numerical simulation of a passively mode-locked Yb-doped fiber laser by a non-distributed model.The characteristics of soliton evolution in a wave-breaking-free regime are nu...We focus on several aspects concerning the numerical simulation of a passively mode-locked Yb-doped fiber laser by a non-distributed model.The characteristics of soliton evolution in a wave-breaking-free regime are numerically investigated with the split-step Fourier method.Based on the model,a parabolic-shaped soliton with a nearly linear chirp and bound soliton pairs are obtained by controlling the intra-cavity average dispersion of the fiber laser.A phenomenon is observed that by keeping the system parameters unchanged,linearly chirped parabolic soliton and bound soliton pairs are attainable under different initial conditions in the transient region between these two kinds of solitons.展开更多
Spinodal decomposition (SD) with different grain boundaries (GBs) is investigated on the atomic scale using the novel phase field crystal model.It is demonstrated that the decomposition process is initiated by precipi...Spinodal decomposition (SD) with different grain boundaries (GBs) is investigated on the atomic scale using the novel phase field crystal model.It is demonstrated that the decomposition process is initiated by precipitating one phase with a larger lattice constant in the tension region at the GBs and the other one with a smaller lattice constant in the compression region.As the phase separation proceeds,the dislocations comprising the low-angle GBs migrate toward the compositional domain boundaries to relieve the coherent strain energy,and eventually become randomly distributed in the coarsening regime of SD,which leads to the disappearance of the low-angle GBs.For high-angle GBs,the location of GBs remains unchanged,while the atoms rearrange along the GBs to fit the stress field arising from compositional inhomogeneity.展开更多
The Nb_(3)Sn thin film cavity,having the potential to be operated at a higher temperature and higher gradient compared to the cavity made from bulk niobium,is one of the most promising key technologies for the nextgen...The Nb_(3)Sn thin film cavity,having the potential to be operated at a higher temperature and higher gradient compared to the cavity made from bulk niobium,is one of the most promising key technologies for the nextgeneration radio-frequency superconducting accelerators.In our work,several 1.3 GHz single-cell TESLA-shaped Nb_(3)Sn thin film cavities,coated by the vapor diffusion method,were tested at Peking University and Institute of Modern Physics,Chinese Academy of Sciences.It was observed that the performance of the Nb_(3)Sn thin film cavities in the tests without the slow cooling down procedure and the effective magnetic field shielding was significantly improved by using a low temperature baking at 100℃for 48 hours.Although the peak electric field of the cavity remained unchanged,the rapid drop of the unloaded Q value(Q0)with the increasing accelerating field(Q-slope)was effectively eliminated,resulting in an improvement of the Q0 in the intermediate field region by~8 times.Furthermore,under better test conditions with the shielded magnetic field less than 5 mG and the slow cooling down procedure in the temperature range of 25-15 K,the Q0 was still improved by about 20%.Our study shows that the low temperature baking can be an effective supplement to the effective post-treatment for the Nb_(3)Sn thin film cavity.展开更多
Low temperature epitaxial growth of ZnO films is achieved on Si(001)substrates by reactive electron beam evap oration.Growth temperature is varied from 125 C to 420 C and the optimum temperature is found between 200...Low temperature epitaxial growth of ZnO films is achieved on Si(001)substrates by reactive electron beam evap oration.Growth temperature is varied from 125 C to 420 C and the optimum temperature is found between 200°C and 300 C.X-ray diffraction shows that the ZnO films are highly c-axis oriented and the line width of(002)diffraction peak is significantly smaller than that measured from the ZnO films deposited by magnetron sput tering.The combined photoluminescence and photoluminescence excitation(PLE)spectroscopic measurements demonstrate the sharp band-absorption edge and exciton absorption in the ZnO films.PLE has also revealed that the absorption characteristic near the band edge is remarkably improved with the increase of oxygen content in the ZnO films,although x-ray diffraction analysis shows that the crystalline structure of ZnO films grown under different oxygen pressures remains unchanged.展开更多
Orphan genes(OGs),which are genes unique to a specific taxon,play a vital role in primary metabolism.However,little is known about the functional significance of Brassica rapa OGs(BrOGs)that were identified in our pre...Orphan genes(OGs),which are genes unique to a specific taxon,play a vital role in primary metabolism.However,little is known about the functional significance of Brassica rapa OGs(BrOGs)that were identified in our previous study.To study their biological functions,we developed a BrOG overexpression(BrOGOE)mutant library of 43 genes in Arabidopsis thaliana and assessed the phenotypic variation of the plants.We found that 19 of the 43 BrOGOE mutants displayed a mutant phenotype and 42 showed a variable soluble sugar content.One mutant,BrOG1OE,with significantly elevated fructose,glucose,and total sugar contents but a reduced sucrose content,was selected for indepth analysis.BrOG1OE showed reduced expression and activity of the Arabidopsis sucrose synthase gene(AtSUS);however,the activity of invertase was unchanged.In contrast,silencing of two copies of BrOG1 in B.rapa,BraA08002322(BrOG1A)and BraSca000221(BrOG1B),by the use of an efficient CRISPR/Cas9 system of Chinese cabbage(B.rapa ssp.campestris)resulted in decreased fructose,glucose,and total soluble sugar contents because of the upregulation of BrSUS1b,BrSUS3,and,specifically,the BrSUS5 gene in the edited BrOG1 transgenic line.In addition,we observed increased sucrose content and SUS activity in the BrOG1 mutants,with the activity of invertase remaining unchanged.Thus,BrOG1 probably affected soluble sugar metabolism in a SUS-dependent manner.This is the first report investigating the function of BrOGs with respect to soluble sugar metabolism and reinforced the idea that OGs are a valuable resource for nutrient metabolism.展开更多
Herein we report on the deposition of transparent hydrophobic thin coatings by radio frequency plasma polymerization(PP) of perfluorooctyl ethylene(PFOE) in both pulsed and continuous wave(CW) modes.The chemical...Herein we report on the deposition of transparent hydrophobic thin coatings by radio frequency plasma polymerization(PP) of perfluorooctyl ethylene(PFOE) in both pulsed and continuous wave(CW) modes.The chemical compositions of the resulting PP-PFOE coatings were confirmed by means of Fourier transform infrared spectroscopy(FT-IR) and X-ray photoelectron spectroscopy(XPS).The thicknesses and surface morphologies of the coatings were examined using surface plasmon resonance spectroscopy and atomic force microscopy.The surface wetting properties and optical transmittance were measured using a water contact angle goniometer and UV-vis spectroscopy.The FT-IR and XPS data showed that the PP-PFOE coatings deposited in the pulsed mode had a higher retention of CF_2 groups compared to those from the CW mode.While the water contact angle of the freshly deposited PP-PFOE from the pulsed mode showed a decrease from 120 degrees to 111 degrees in the first two days,it then remained almost unchanged up to 45 days.The UV-vis data indicated that a PP-PFOE coating 30.6 nm thick had a light transmittance above 90%in the UV and visible ranges.The deposition rates under various plasma conditions are also discussed.展开更多
文摘40 years ago,a small collective economic workshop was set up in Shijie Town(now Shijie Street)in Ningbo,called Youth Garment Factory.Today,40 years later,this small workshop has already become a company with more than 50,000 employees and an annual output of 50 million shirts and a revenue of 87.9 billion yuan in 2018,Youngor,a Chinese top 500 enterprise that spans textile,clothing,real estate,investment and trade.
文摘May 23 marks the 43rd anniversary of the peaceful liberation of Tibet.A spokesman for the United Front Work Department of the CPC Central Commit-tee recently spoke to a Xinhua reporter on development and construction in the Tibet Autonomous Region and the cen-tral government's policy on the Dalai L ama.
基金supported by Lundbeckfonden(R250-2017-134,to HHJ).
文摘When calcium ions enter the cytosol,it is a stimulatory signal for cellular events.The calcium sensor calmodulin picks up the change in calcium concentration and relays this information to its more than 300 downstream interaction partners.In this way,calmodulin affects cellular processes such as fertilization,muscle contraction,neuronal firing,and apoptosis.That is,calmodulin is involved in(nearly)everything!The significance of calmodulin is emphasized by the fact that we all carry three different genes(CALM1,2,3)on different chromosomes that encode the exact same calmodulin protein,and these are all expressed in all cell types.Moreover,throughout vertebrate evolution,the protein sequence has remained completely unchanged.
文摘No matter how the world changes,people’s aspiration for a better living environment remains unchanged.Urban planners factor this in their blueprints and different eras give different characteristics to urban design and architecture.Modernization,technological progress,cultural trends,and social issues have all become drivers of urban planning and building design.In addition,architects and urban planners worldwide have to consider several crucial issues today-how to tackle climate change by reducing carbon emission in construction and improving the ecological environment in urban design,how to revitalize ancient cultural heritage,and how to create a new,sustainable urban culture.
文摘As shown in the results of the survey of the confidence of 100 Chinese economists,conducted by China’s Economic Monitoring and Analysis Centre,National Bureau of Statistics,the confidence index of the economists in the second quarter of 2009 was 5.60,the range of possible indices being from 1 to 9.It was 1.63 points higher than that of the first quarter,continuing the stabilized situation with a trend of rising again.The situation had appeared since the beginning of 2009.
文摘Physical activity has many benefits for individual health and well-being,including a reduced risk of noncommunicable diseases,as well as improved mental health,sleep,and cognitive function.1 Being physically active also has broader social and environmental benefits and has a key role to play in achieving the 2030 Sustainable Development Goals.2,3 However,over 80%of adolescents and around a quarter of adults are insufficiently active and these figures have remained largely unchanged for the past 20 years.4,5 A recent economic analysis estimated that the total cost of inactive lifestyles equates to USD 27 billion(INT 48 billion)annually.
文摘At the recent routine press conference of the CCPIT in October, CCPIT spokesperson Zhang Xin stated that China’s foreign trade operated smoothly for the first three quarters of this year, with a year-on-year growth rate that remained basically unchanged and showed a positive development trend.
文摘IN an ancient town in the southern reaches of the Yangtze River there lived in a small compound of nine average households sharing an ancient well.e layout of the oldstyle houses had largely remained unchanged over the years, except that more and more modern furniture and home décor accessories had been added.
文摘China’s policy of reform and opening up will remain unchanged over the long term.——Chinese President Xi Jinping April 13,2023 while inspecting Guangdong Province Measures of high-standard opening up Xi noted,in his report to the 20th CPC National Congress,that in order to promote high-standard opening up,China will·leverage the strengths of China’s enormous market,attract global resources and production factors with our strong domestic economy,and amplify the interplay between domestic and international markets and resources.
基金The research was supported by the National Natural Science Foundation of China(No.31500205,No.31770644,and No.81703656)Scientific Research Fund of Sichuan Provincial Education Department(No.17ZB0456 and No.13TD0023)+2 种基金Yunnan Engineering Laboratory for Agro-environment Pollution Control and Eco-remediation/The Innovation Team for Farmland Non-pollution Production of Yunnan Province(No.2017HC015)the doctoral Fund Project(No.14zx7157 and No.13zx7116)Longshan academic talent research supporting program(No.17LZXT09)of Southwest University of Science and Technology.
文摘The flavonoid compounds are important secondary metabolites with versatile human nutritive benefits and fulfill a multitude of functions during plant growth and development.The abundance of different flavonoid compounds are finely tuned with species-specific pattern by a ternary MBW complex,which consists of a MYB,a bHLH,and a WD40 protein,but the essential role of SlAN11,which is a WD40 protein,is not fully understood in tomato until now.In this study,a tomato WD40 protein named as SlAN11 was characterized as an effective transcription regulator to promote plant anthocyanin and seed proanthocyanidin(PA)contents,with late flavonoid biosynthetic genes activated in 35S::SlAN11 transgenic lines,while the dihydroflavonol flow to the accumulation of flavonols or their glycosylated derivatives was reduced by repressing the expression of SlFLS in this SlAN11-overexpressed lines.The above changes were reversed in 35S::SlAN11-RNAi transgenic lines except remained levels of flavonol compounds and SlFLS expression.Interestingly,our data revealed that SlAN11 gene could affect seed dormancy by regulating the expressions of abscisic acid(ABA)signaling-related genes SlABI3 and SlABI5,and the sensitivity to ABA treatment in seed germination is conversely changed by SlAN11-overexpressed or-downregulated lines.Yeast two-hybrid assays demonstrated that SlAN11 interacted with bHLH but not with MYB proteins in the ternary MBW complex,whereas bHLH interacted with MYB in tomato.Our results indicated that low level of anthocyanins in tomato fruits,with low expression of bHLH(SlTT8)and MYB(SlANT1 and SlAN2)genes,remain unchanged upon modification of SlAN11 gene alone in the transgenic lines.These results suggest that the tomato WD40 protein SlAN11,coordinating with bHLH and MYB proteins,plays a crucial role in the fine adjustment of the flavonoid biosynthesis and seed dormancy in tomato.
文摘DC stray current can cause severe corrosion on buried pipelines.In this study,firstly,we deduced the equation of DC stray current interference on pipelines.Next,the cathode boundary condition was discretized with pipe elements,and corresponding experiments were designed to validate the mathematical model.Finally,the numerical simulation program BEASY was used to study the corrosion effect of DC stray current that an auxiliary anode bed generated in an impressed current cathodic protection system.The effects of crossing angle,crossing distance,distance of the two pipelines,anode output current,depth,and soil resistivity were investigated.Our results indicate that pipeline crossing substantially affects the corrosion potential of both protected and unprotected pipelines.Pipeline crossing angles,crossing distances,and anode depths,our results suggest,have no significant influence.Decreasing anode output current or soil resistivity reduces pipeline corrosion gradually.A reduction of corrosion also occurs when the distance between two parallel pipelines increases.
文摘This erratum1 is issued by the authors to note that part(b)of Fig.1 was erroneously excluded in the published version of the manuscript.A correct version of Fig.1 is provided here.The figure caption of Fig.1 is repeated here,however the captions and text of the document remain unchanged.
文摘Jack London(1876-1916) is known as an American novelist in the early 20 th century. He lived in the gilded times that were full of different kinds of trend of thought in literature and art. His experiences made his life more colorful. He saw the cruelty of Capitalism and spoke for Socialism with his words. His novels, The Call of the Wild, The leading character, in their own way, witnessed the survival of the fittest in their life. Jack London told the unchanged truth — the survival of the fittest in his brilliant words. It is difficult to change the world, but easy to change oneself. One adjusts to his life space with his"evolution",and one goes in a new environment where every cloud has a silver lining.
基金by the National Natural Science Foundation of China and Scientific Forefront and Interdisciplinary Innovation Project,Jilin University under Grant Nos 60372061 and 200903296.
文摘We focus on several aspects concerning the numerical simulation of a passively mode-locked Yb-doped fiber laser by a non-distributed model.The characteristics of soliton evolution in a wave-breaking-free regime are numerically investigated with the split-step Fourier method.Based on the model,a parabolic-shaped soliton with a nearly linear chirp and bound soliton pairs are obtained by controlling the intra-cavity average dispersion of the fiber laser.A phenomenon is observed that by keeping the system parameters unchanged,linearly chirped parabolic soliton and bound soliton pairs are attainable under different initial conditions in the transient region between these two kinds of solitons.
基金Supported by the National Natural Science Foundation of China under Grant Nos 51174168,51075335 and 10902086the Graduate Starting Seed Fund of NPU under Grant No Z2012025the NPU Foundation for Fundamental Research under Grant Nos JC201109 and JC201005。
文摘Spinodal decomposition (SD) with different grain boundaries (GBs) is investigated on the atomic scale using the novel phase field crystal model.It is demonstrated that the decomposition process is initiated by precipitating one phase with a larger lattice constant in the tension region at the GBs and the other one with a smaller lattice constant in the compression region.As the phase separation proceeds,the dislocations comprising the low-angle GBs migrate toward the compositional domain boundaries to relieve the coherent strain energy,and eventually become randomly distributed in the coarsening regime of SD,which leads to the disappearance of the low-angle GBs.For high-angle GBs,the location of GBs remains unchanged,while the atoms rearrange along the GBs to fit the stress field arising from compositional inhomogeneity.
基金Supported by the Youth Innovation Promotion Association of Chinese Academy of Sciences(Grant No.2020410)the Major Research Plan of National Natural Science Foundation of China(Grant No.91426303)+1 种基金the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB25000000)the National Postdoctoral Program for Innovative Talents(Grant No.BX201700257).
文摘The Nb_(3)Sn thin film cavity,having the potential to be operated at a higher temperature and higher gradient compared to the cavity made from bulk niobium,is one of the most promising key technologies for the nextgeneration radio-frequency superconducting accelerators.In our work,several 1.3 GHz single-cell TESLA-shaped Nb_(3)Sn thin film cavities,coated by the vapor diffusion method,were tested at Peking University and Institute of Modern Physics,Chinese Academy of Sciences.It was observed that the performance of the Nb_(3)Sn thin film cavities in the tests without the slow cooling down procedure and the effective magnetic field shielding was significantly improved by using a low temperature baking at 100℃for 48 hours.Although the peak electric field of the cavity remained unchanged,the rapid drop of the unloaded Q value(Q0)with the increasing accelerating field(Q-slope)was effectively eliminated,resulting in an improvement of the Q0 in the intermediate field region by~8 times.Furthermore,under better test conditions with the shielded magnetic field less than 5 mG and the slow cooling down procedure in the temperature range of 25-15 K,the Q0 was still improved by about 20%.Our study shows that the low temperature baking can be an effective supplement to the effective post-treatment for the Nb_(3)Sn thin film cavity.
基金Supported by the National Natural Science Foundation of China under Grant No.69606006Natural Science Fund of Zhejiang Province.
文摘Low temperature epitaxial growth of ZnO films is achieved on Si(001)substrates by reactive electron beam evap oration.Growth temperature is varied from 125 C to 420 C and the optimum temperature is found between 200°C and 300 C.X-ray diffraction shows that the ZnO films are highly c-axis oriented and the line width of(002)diffraction peak is significantly smaller than that measured from the ZnO films deposited by magnetron sput tering.The combined photoluminescence and photoluminescence excitation(PLE)spectroscopic measurements demonstrate the sharp band-absorption edge and exciton absorption in the ZnO films.PLE has also revealed that the absorption characteristic near the band edge is remarkably improved with the increase of oxygen content in the ZnO films,although x-ray diffraction analysis shows that the crystalline structure of ZnO films grown under different oxygen pressures remains unchanged.
基金supported by the National Natural Science Foundation of China(31772326)the National Key Research and Development Program of China(2017YFD0101802).
文摘Orphan genes(OGs),which are genes unique to a specific taxon,play a vital role in primary metabolism.However,little is known about the functional significance of Brassica rapa OGs(BrOGs)that were identified in our previous study.To study their biological functions,we developed a BrOG overexpression(BrOGOE)mutant library of 43 genes in Arabidopsis thaliana and assessed the phenotypic variation of the plants.We found that 19 of the 43 BrOGOE mutants displayed a mutant phenotype and 42 showed a variable soluble sugar content.One mutant,BrOG1OE,with significantly elevated fructose,glucose,and total sugar contents but a reduced sucrose content,was selected for indepth analysis.BrOG1OE showed reduced expression and activity of the Arabidopsis sucrose synthase gene(AtSUS);however,the activity of invertase was unchanged.In contrast,silencing of two copies of BrOG1 in B.rapa,BraA08002322(BrOG1A)and BraSca000221(BrOG1B),by the use of an efficient CRISPR/Cas9 system of Chinese cabbage(B.rapa ssp.campestris)resulted in decreased fructose,glucose,and total soluble sugar contents because of the upregulation of BrSUS1b,BrSUS3,and,specifically,the BrSUS5 gene in the edited BrOG1 transgenic line.In addition,we observed increased sucrose content and SUS activity in the BrOG1 mutants,with the activity of invertase remaining unchanged.Thus,BrOG1 probably affected soluble sugar metabolism in a SUS-dependent manner.This is the first report investigating the function of BrOGs with respect to soluble sugar metabolism and reinforced the idea that OGs are a valuable resource for nutrient metabolism.
基金supported by the Tianjin Research Program of Application Foundation and Advanced Technology,China(No.12JCYBJC31700)the Program for New Century Excellent Talents in University,China(No.NCET-12-1064)
文摘Herein we report on the deposition of transparent hydrophobic thin coatings by radio frequency plasma polymerization(PP) of perfluorooctyl ethylene(PFOE) in both pulsed and continuous wave(CW) modes.The chemical compositions of the resulting PP-PFOE coatings were confirmed by means of Fourier transform infrared spectroscopy(FT-IR) and X-ray photoelectron spectroscopy(XPS).The thicknesses and surface morphologies of the coatings were examined using surface plasmon resonance spectroscopy and atomic force microscopy.The surface wetting properties and optical transmittance were measured using a water contact angle goniometer and UV-vis spectroscopy.The FT-IR and XPS data showed that the PP-PFOE coatings deposited in the pulsed mode had a higher retention of CF_2 groups compared to those from the CW mode.While the water contact angle of the freshly deposited PP-PFOE from the pulsed mode showed a decrease from 120 degrees to 111 degrees in the first two days,it then remained almost unchanged up to 45 days.The UV-vis data indicated that a PP-PFOE coating 30.6 nm thick had a light transmittance above 90%in the UV and visible ranges.The deposition rates under various plasma conditions are also discussed.